Milling/rebatching is all I did before I started making my own CP...only I used a friend's soap to do it. I've heard of a lot of people using the process you mentioned lately. Rebatched soap is wonderful to use, however, lots of people think it isn't as 'pretty' as CP soap can be. It can look pretty rustic, but with some practice, I was even able to get swirls in rebatched soap. The benefits...it can be used immediately, just as HP soap can. If done properly and not too much liquid added, the time it takes to dry out completely isn't long at all.